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Cylinder drop test spark?

N

Nick0151

Regular Contributor
Hi guys,

needed to flush motor after being in the salt water.. after flooding it few time over the weekend thought I’d do a drop test see if firing on all three I think it is but when plugs pulled as you ca see in the video below the is large spark coming from the HT lead.

Does this drop test sound right to you and what to you think of the arc.

Thanks again in advance


 
Cylinder has good spark.----But you might consider replacing wire boots.-----What about the other 2 cylinders ?--Post video of them if you like.------Do a compression test for future reference.------Post the numbers here.
 
I should have posted the other two yes much more noticeable drop when they are pulled il pop back out and do one.
I don’t have a compression tester il order one now from Amazon.

Do you think it’s running ok?
 
On a 40 year old motor keeping an eye on compression is key.------Lots of iffy compression testers on Amazon.----Best to get one at a local automotive store.----Allways run fuel out of carburetors when boat goes on the trailer.-----Empty carburetors stay clean.
 
I think I can hear the change with plug wire disconnected/re-connected, meaning it is firing. Probably not equal with others though. That can be normal or due to several other things. I wouldn't be concerned if everything else checks out ok.
 
Here is the other ones too

I ordered one before reading that post it had 4 half stars see how it goes.

Thanks for all the advice!!

 
Remove the cylinder head.-----You have a bad head gasket perhaps.-----But likely scored pistons and motor needs a rebuild.-----Not likely the answer you wanted , but it is the answer you needed.
 
The motor likely sounded good to you.------But I have heard good ones run.-----Bought 21 of those at one time nearly 30 years ago.
 
Right just redone the compression test after watching YouTube and realising I don’t do it right. This time with engine still cold I opened the throttle plates and got the following still not great but did it twice to make sure they are ;

1-125psi
2-130psi
3-150psi

Any better?
 
Just stop jumping around and take the head off.-----Your motor needs repairs.---Just not what you want to hear I guess.
 
Don’t really want to take it off your right 😂 but worried if I do take it off I need a new head gasket il have to order one before I tackle it..

Is it hard to do?
 
???---Head gaskets are cheap !-----Amazing how some folks will install new electronic parts that cost many beer tokens.----But are scared to remove a cylinder head.----Just 22 bolts I think and it is off.----Nothing to it.
 
im trusting you on this one racerone found head gasket for £35 about $40 have to say the parts over the pond are definitely more abundant and cheaper..
 
Guys iv started now and the 4 bolts in the photo I can’t get them off I’m worried il brake something. Iv tried heat and hitting with hammer to try to shock it. Not sure how much heat I can apply. The other 14 have all loosened fine

Any tricks you may know of?

32D7DBA4-7AF8-4025-B383-A91B9C4C9F41.jpeg
 
Well Racerone hats off to you!

Outboard is back together ran great (in barrel)

Ran for about half hour and done compression test…

We now have ;

1-127ish between 125 and 130
2- 130
3-130

😁

Thanks for all the help and advice!
 
Racer or anyone that may know did the drop test again and it’s still near on the same as in the video, I can tell something happens when removed and connected again but not as noticeable as 2 or 3 compression is spot on tbf spark is great still. Temp with IR thermometer is about 62c 140 f ish over the water jacket and head.

Could it be bad reeds for cylinder number one? When I got the motor I noticed fuel out of #1 I have a video of it last year?

Thanks in advance
 
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